1. Field of the Invention
The present invention relates to surgical knives.
2. Description of the Prior Art
Surgical scalpels have been proposed having a sapphire blade. An argon laser is coupled to the blade and energised to inject its high intensity light output into the immediately adjacent region of tissue being incised. The blue green light of the laser is selectively absorbed by the red haemoglobin of the blood in the walls of the incised tissue and rapid coagulation occurs to seal the walls of the incision.
A disadvantage of such scalpels is that the laser subjects the sapphire to thermal shock and these shocks promote cracks in the sapphire thereby reducing the life of the blade.
The solution to this problem has been to provide blades of softer material such as fused silica. However, while this has tended to extend the life of the blade with regard to cracking, blades of softer material wear more rapidly than harder materials and this in turn acts to limit the life of the blade.
Thus, it is an object of the invention to provide an improved surgical knife.